A torque fluctuation absorbing apparatus, for example which is mounted on a hybrid driving apparatus including an engine and an electric motor as power sources, is provided at an output shaft of the engine and/or of the electric motor and absorbs (controls) a fluctuating torque generated by the engine and the electric motor. A known art of the torque fluctuation absorbing apparatus is disclosed in Japanese Patent No. 2002-13547 (hereinafter, referred to as reference 1). The torque fluctuation absorbing apparatus (a damper for a hybrid driving apparatus) disclosed in reference 1 includes a limiter mechanism which intercepts a power transmittance when a fluctuating torque generated by first and second power source achieves a predetermined value. The limiter mechanism is configured to allow a slip of a torsion member which controls the fluctuating torque generated between a first rotation member rotatably driven by the first power source and a second rotation member connected to the second power source, when the fluctuating torque between the first and second rotation members achieves the predetermined value, hence an excessive torque is prevented from being inputted from the first rotation member to the second rotation member.
According to the torque fluctuation absorbing apparatus (the damper for the hybrid driving apparatus) disclosed in the reference 1, in order to ensure a required limit torque in response to an increase of an output of the engine, the size of the torsion member is required to be larger. In the mean time, a size of a disc spring, which presses and connects the torsion member to the first and second rotation members, also becomes larger. Accordingly, an entire size of the torque fluctuation absorbing apparatus may be increased, and downsizing the apparatus may be difficult. Especially, when the size of the torque fluctuation absorbing apparatus is increased for ensuring the required limit torque value, it may be difficult to mount the torque fluctuation absorbing apparatus on an FF-type vehicle which includes a large space in an axial direction and requires to constrain space.
A need thus exists for a torque fluctuation absorbing apparatus which is not susceptible to the drawback mentioned above.